THE EVIDENCE FROM MISSING LINKS. 



163 



queries. A considerable number of fossil reptiles are ranked to form 

 a distinct order or division, marked by various near approaches to 

 the structure of birds. A single example of this curious group will 

 suffice to show the intermediate nature of its included forms. Once 

 again the Lithographic Slates of Solenhofen yield a rich reward to 

 geological investigation, and present us with the fossil skeleton of an 

 animal which in the flesh attained a length of about two feet. This 

 is the Compsognathus (Fig. 84) of the geologist a long-necked reptile, 

 possessing a small head, the jaws of which, however, were armed with 

 teeth. Its fore limbs were short, its hind limbs being long and bird- 

 like. Like that of birds, its thigh-bone (Fig. 85, x,fe) is shorter than 

 its leg-bone. As in birds (Fig. 85 A), the upper half of the ankle- 

 bone of Compsognathus (Fig. 85, B, as, ca) unites with the lower part 

 of the leg ; but the lower half of the ankle (td) was not, as in birds, 

 united with the instep-bones, or metatarsals (i, 2, 3, 4), which are 

 three or four in number, long and slender, and which, in Compsogna- 

 thus, support the second, third, and fourth toes. A mere trace of the 

 instep-bone of the fifth toe exists, and the first or great toe is of 

 small size. In all birds the fifth toe is entirely wanting. Looking 

 at the structure of Compsognathus, and of its fossil allies, such as 

 Iguanodon, little or no doubt can be entertained that these reptiles 

 were capable of resting on their hind limbs, in bird-like fashion, and 

 of walking, or hopping, after the fashion of the feathered bipeds, to 



FIG. 85. (A) HINDLIMBS OF BIRD ; (B) EXTINCT REPTILE; AND (C) CROCODILE. 



which indeed, by a use of the imagination, strictly scientific, we may 

 regard this reptilian group as having in due time given origin. It 

 is unquestionably to the struthious birds, that is, to the ostriches and 



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